/*********************************************************************************
 *                                                                               *
 * The MIT License (MIT)                                                         *
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 * Copyright (c) 2015-2022 aoju.org OSHI and other contributors.                 *
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package org.aoju.bus.health.unix.openbsd;

import org.aoju.bus.core.annotation.ThreadSafe;
import org.aoju.bus.core.lang.RegEx;
import org.aoju.bus.health.Executor;

import java.util.List;

/**
 * Reads from fstat.
 *
 * @author Kimi Liu
 * @version 6.5.0
 * @since Java 17+
 */
@ThreadSafe
public final class FstatKit {

    /**
     * Gets current working directory info (using {@code ps} actually).
     *
     * @param pid a process ID
     * @return the current working directory for that process.
     */
    public static String getCwd(int pid) {
        List<String> ps = Executor.runNative("ps -axwwo cwd -p " + pid);
        if (ps.size() > 1) {
            return ps.get(1);
        }
        return "";
    }

    /**
     * Gets open number of files.
     *
     * @param pid The process ID
     * @return the number of open files.
     */
    public static long getOpenFiles(int pid) {
        long fd = 0L;
        List<String> fstat = Executor.runNative("fstat -sp " + pid);
        for (String line : fstat) {
            String[] split = RegEx.SPACES.split(line.trim(), 11);
            if (split.length == 11 && !"pipe".contains(split[4]) && !"unix".contains(split[4])) {
                fd++;
            }
        }
        // subtract 1 for header row
        return fd - 1;
    }

}
